Merge pull request #851 from iceljc/master

fix cost calculation

Author: iceljc

src/Infrastructure/BotSharp.Core/Conversations/Services/TokenStatistics.cs

@@ -42,7 +42,8 @@ public void AddToken(TokenStatsModel stats, RoleDialogModel message)
         var settings = settingsService.GetSetting(stats.Provider, _model);
 
         var deltaPromptCost = stats.PromptCount / 1000f * settings.PromptCost;
-        var deltaCompletionCost = stats.CompletionCount / 1000 * settings.CompletionCost;
+        var deltaCompletionCost = stats.CompletionCount / 1000f * settings.CompletionCost;
+        var deltaTotal = deltaPromptCost + deltaCompletionCost;
         _promptCost += deltaPromptCost;
         _completionCost += deltaCompletionCost;
 
@@ -55,10 +56,10 @@ public void AddToken(TokenStatsModel stats, RoleDialogModel message)
 
         // Total cost
         var total_cost = float.Parse(stat.GetState("llm_total_cost", "0"));
-        total_cost += Cost;
+        total_cost += deltaTotal;
         stat.SetState("llm_total_cost", total_cost, isNeedVersion: false, source: StateSource.Application);
 
-
+        // Save stats
         var globalStats = _services.GetRequiredService<IBotSharpStatsService>();
         var body = new BotSharpStatsInput
         {